You can generate a new copy of your license with the form above. Fluid has always been available for purchase via PayPal. That means you purchased Fluid via PayPal. Enter the email address associated with your PayPal account above, and a new Fluid license will be automatically generated and sent to your email address.
Please note that after 11 years of free updates, I decided to make Fluid 2.0 a paid upgrade. If you purchased your license before July, 2018, then you purchased a Fluid 1.x license which will not work with the current version of Fluid (2.x).
Tip: Fluid's license format is a file with a file extension of fluidlicense (for Fluid 1.x) or fluid2license (for Fluid 2.x). You can easily copy and back up this license file yourself. I recommend you do so. Also, your original license email (including the attached the license file) may still be stored in your email client. Please check there too.